ML16307A013

Issuance of Amendment Regarding Revision to the Fire Protection Program Related to Cable Separation in Containment

ML16307A013
Person / Time
Site:	Watts Bar
Issue date:	12/12/2016
From:	Robert Schaaf Plant Licensing Branch II
To:	James Shea Tennessee Valley Authority
Schaaf R,, DORL/LPL-2, 415-6020
References
CAC MF7413
Download: ML16307A013 (15)

Text

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 December 12, 2016 Mr. Joseph W. Shea Vice President, Nuclear Licensing Tennessee Valley Authority 1101 Market Street, LP 3R-C Chattanooga, TN 37402-2801

SUBJECT:

WATTS BAR NUCLEAR PLANT, UNIT 1 - ISSUANCE OF AMENDMENT REGARDING REVISION TO THE FIRE PROTECTION PROGRAM RELATED TO CABLE SEPARATION IN CONTAINMENT (CAC NO. MF7413)

Dear Mr. Shea:

The U.S. Nuclear Regulatory Commission has issued the enclosed Amendment No. 108 to Facility Operating License No. NPF-90 for the Watts Bar Nuclear Plant (WBN), Unit 1. This amendment consists of changes to the license in response to your application dated February 23, 2016, as supplemented by letter dated July 22, 2016.

The amendment revises the Fire Protection Program for WBN, Unit 1; and revises Paragraph 2.F in the Facility Operating License.

A copy of the related Safety Evaluation is also enclosed. The Notice of Issuance will be included in the Commission's biweekly Federal Register notice. If you have any questions regarding this letter, please contact me at (301) 415-6020.

Sincerely,

Ul-!R~/

Robert G. Schaaf, Senior Proj,ct Manager Plant Licensing Branch 11-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation Docket No. 50-390

Enclosures:

1. Amendment No. 108 to NPF-90

2. Safety Evaluation cc w/encls: Distribution via Listserv

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 TENNESSEE VALLEY AUTHORITY DOCKET NO. 50-390 WATTS BAR NUCLEAR PLANT. UNIT 1 AMENDMENT TO FACILITY OPERATING LICENSE Amendment No. 108 License No. NPF-90

1. The Nuclear Regulatory Commission (the Commission) has found that:

A. The application for amendment by the Tennessee Valley Authority (the licensee) dated February 23, 2016, as supplemented by letter dated July 22, 2016, complies with the standards and requirements of the Atomic Energy Act of 1954, as amended (the Act), and the Commission's rules and regulations set forth in 10 CFR Chapter I; B. The facility will operate in conformity with the application, the provisions of the Act, and the rules and regulations of the Commission; C. There is reasonable assurance (i) that the activities authorized by this amendment can be conducted without endangering the health and safety of the public, and (ii) that such activities will be conducted in compliance with the Commission's regulations; D. The issuance of this amendment will not be inimical to the common defense and security or to the health and safety of the public; and E. The issuance of this amendment is in accordance with 10 CFR Part 51 of the Commission's regulations and all applicable requirements have been satisfied.

Enclosure 1

2. Accordingly, the Facility Operating License No. NPF-90 is amended by changes to paragraphs 2.C.(2) and 2.F, as indicated in the attachment to this license amendment.

3. This license amendment is effective as of the date of its issuance, and shall be implemented within 30 days of issuance.

FOR THE NUCLEAR REGULATORY COMMISSION

~i?~ng Chief Plant Licensing Branch 11-2 Division of Operating Reactor Licensing Office of Nuclear Reactor Regulation

Attachment:

Changes to the Operating License Date of Issuance: December 12, Xl16

ATTACHMENT TO LICENSE AMENDMENT NO. 108 WATTS BAR NUCLEAR PLANT, UNIT 1 FACILITY OPERATING LICENSE NO. NPF-90 DOCKET NO. 50-390 Replace the following pages of Facility Operating License NPF-90 with the attached revised pages. The revised pages are identified by amendment number and contain marginal lines indicating the areas of change.

REMOVE INSERT 3 3 5a 5a

(4) TVA, pursuant to the Act and 10 CFR Parts 30, 40 and 70, to receive, possess, and use in amounts as required, any byproduct, source or special nuclear material without restriction to chemical or physical form, for sample analysis, instrument calibration, or other activity associated with radioactive apparatus or components; and (5) TVA, pursuant to the Act and 10 CFR Parts 30, 40 and 70, to possess, but not separate, such byproduct and special nuclear materials as may be produced by the operation of the facility.

C. This license shall be deemed to contain and is subject to the conditions specified in the Commission's regulations set forth in 10 CFR Chapter I and is subject to all applicable provisions of the Act and to the rules, regulations, and orders of the Commission now or hereafter in effect, and is subject to the additional conditions specified or incorporated below.

(1) Maximum Power Level TVA is authorized to operate the facility at reactor core power levels not in excess of 3459 megawatts thermal.

(2) Technical Specifications and Environmental Protection Plan The Technical Specifications contained in Appendix A as revised through Amendment No. 108 and the Environmental Protection Plan contained in Appendix B, both of which are attached hereto, are hereby incorporated into this license. TVA shall operate the facility in accordance with the Technical Specifications and the Environmental Protection Plan.

(3) Safety Parameter Display System (SPDS) (Section 18.2 of SER Supplements 5 and 15)

Prior to startup following the first refueling outage, TVA shall accomplish the necessary activities, provide acceptable responses, and implement all proposed corrective actions related to having the Watts Bar Unit 1 SPDS operational.

(4) Vehicle Bomb Control Program (Section 13.6.9 of SSER 20)

During the period of the exemption granted in paragraph 2.D.(3) of this license, in implementing the power ascension phase of the approved initial test program, TVA shall not exceed 50% power until the requirements of 10 CFR 73.55(c)(7) and (8) are fully implemented. TVA shall submit a letter under oath or affirmation when the requirements of 73.55(c)(7) and (8) have been fully implemented.

Facility License No. NPF-90 Amendment No. 108

5a F. TVA shall implement and maintain in effect all provisions of the approved fire protection program as described in the Fire Protection Report for the facility, as approved in Appendix FF Section 3.5 of Supplement 18 and Supplement 29 of the SER (NUREG-0847) and in Amendment No. 108 subject to the following provision:

TVA may make changes to the approved fire protection program without prior approval of the Commission only if those changes would not adversely affect the ability to achieve and maintain safe shutdown in the event of a fire.

G. Deleted H. The licensee shall have and maintain financial protection of such types and in such amounts as the Commission shall require in accordance with Section 170 of the Atomic Energy Act of 1954, as amended, to cover public liability claims.

Facility License No. NPF-90 Amendment No. 8-7 88 QQ ~ 108

UNITED STATES NUCLEAR REGULATORY COMMISSION WASHINGTON, D.C. 20555-0001 SAFETY EVALUATION BY THE OFFICE OF NUCLEAR REACTOR REGULATION RELATED TO AMENDMENT NO. 108 TO FACILITY OPERATING LICENSE NO. NPF-90 TENNESSEE VALLEY AUTHORITY WATTS BAR NUCLEAR PLANT. UNIT 1 DOCKET NO. 50-390

1.0 INTRODUCTION

By application dated February 23, 2016 (Agencywide Documents Access and Management System (ADAMS) Accession No. ML16054A585), as supplemented by letter dated July 22, 2016 (ADAMS Accession No. ML16204A374), the Tennessee Valley Authority (TVA, or the licensee) submitted a license amendment request for the Watts Bar Nuclear Plant (WBN),

Unit 1. The supplemental letter dated July 22, 2016, provided additional information that clarified the application, did not expand the scope of the application as originally noticed, and did not change the NRC staff's original proposed no significant hazards consideration determination as published in the Federal Register on May 10, 2016 (81FR28901).

The proposed amendment would modify the approved Fire Protection Program for WBN, Unit 1.

Specifically, TVA requested Nuclear Regulatory Commission (NRC) review and approval for not meeting the separation criteria of Title 10, Code of Federal Regulations (10 CFR) Part 50, Appendix R, Section 111.G for three cable interactions inside the WBN, Unit 1 containment. A similar request for Unit 2 was reviewed and approved by the NRC staff in Supplemental Safety Evaluation Report (SSER) 29 to NUREG-0847 (ADAMS Accession No. ML15282A051).

2.0 REGULATORY EVALUATION

The Watts Bar Fire Protection Program is documented in the WBN Fire Protection Report (FPR). The as-constructed WBN dual-unit FPR was submitted for NRC review by TVA letters dated June 24, August 27, and October 7, 2015 (ADAMS Accession Nos. ML15175A508, ML15239A794, and ML15280A508, respectively) to support completion of the NRC staff's review of the Operating License application for WBN, Unit 2.

The NRC staff's technical review and approval of the dual-unit FPR was documented in NUREG-0847, "Safety Evaluation Report [SER] Related to the Operation of Watts Bar Nuclear Plant, Unit 2," SSER 29, issued October 2015 (ADAMS Accession No. ML15282A051 ).

Subsequently, on December 23, 2015, the NRC staff approved an amendment to the Unit 1 Enclosure 2

license to reflect the dual-unit Fire Protection Program that was approved in SSER 29 (ADAMS Accession No. ML15344A318).

The WBN Fire Protection Program is not required to comply with 10 CFR Part 50, Appendix R, because the operating licenses for WBN, Units 1 and 2, were not issued prior to January 1, 1979. However, in the NRG-approved FPR, TVA committed to meet Sections 111.G, 111.J, and 111.0, of 10 CFR Part 50, Appendix R, to assure safe shutdown capability. In its application for this amendment, TVA requested NRC approval for proposed deviations from the requirements of 10 CFR Part 50, Appendix R, Section 111.G.2.d for 3 cable interactions inside containment.

3.0 TECHNICAL EVALUATION

TVA committed to maintain safe shutdown capability during and after a fire in accordance with Section 111.G of Appendix R to 10 CFR Part 50. The high level goal of Appendix R separation criteria is to be able to achieve and maintain hot shutdown conditions and be able to achieve and maintain cold shutdown conditions within 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. Section 111.G.2.d of Appendix R to 10 CFR Part 50 indicates that inside non-inerted containments, separation of cables and equipment and associated non-safety circuits of redundant trains by a horizontal distance of more than 20 feet with no intervening combustibles or fire hazards is an acceptable method of ensuring that a redundant train of equipment and circuits are protected from a fire.

TVA stated that in the Unit 1 Reactor Building inside the Crane Wall, equipment required for fire safe shutdown (FSSD) are adequately separated from each other in accordance with 111.G.2.d criterion, except for the following:

• Cables for steam generator 1 hot- and cold-leg temperature indication instruments have less than 20 feet horizontal separation from the corresponding cables for steam generator 3.

• Cables for the reactor head vent valves have less than 20 feet horizontal separation from the pressurizer power-operated relief valve (PORV) cables.

• A control rod drive mechanism (CROM) cooler cable has less than 20 feet horizontal separation from a lower compartment cooler (LCC) cable.

Depending on the configuration of components, these configurations would be subject to the requirements of Sections 111.G.2.d, 111.G.2.e, or 111.G.2.f. Section 111.G.2.d relates to protection by spatial separation of components. Section 111.G.2.e relates to protection by area-wide detection and suppression systems. Section 111.G.2.f relates to protection by installation of radiant energy shields. TVA chose to evaluate these configurations in accordance with Section 111.G.2.d. The NRC staff agrees that Section 111.G.2.d is the logical requirement against which these configurations should be evaluated because the configurations under review most closely match that arrangement.

3.1 Room Description TVA designates the area of the Unit 1 Reactor Building inside the Crane Wall as RI. This area is separated from adjacent areas of the Unit 1 Reactor Building by reinforced concrete barriers

that are from 30 to 48 inches thick. These barriers are not assigned a fire resistance rating and contain unsealed electrical and mechanical penetrations. The room has a floor area of 3,656 square feet and a ceiling height of 40 to 51 feet. TVA further subdivides this area into four quadrants or zones (Rl-1, Rl-2, Rl-3, and Rl-4). The quadrants divide the area radially (moving clockwise from station south) as follows: Rl-1 runs from 0 to 90 degrees, Rl-2 from 90 to 180 degrees, Rl-3 from 180 to 270 degrees, and Rl-4 from 270 to 360 degrees. Each quadrant contains a reactor coolant pump (RCP), the associated steam generator, and a CROM cooler.

3.2 Defense in Depth Features The FPR describes the measures that are established at WBN to implement a defense-in-depth fire protection program in plant areas important to safety. The objectives of these measures are to: (1) prevent fires from starting; (2) detect rapidly, control, and extinguish promptly those fires that do occur; and (3) provide protection for structures, systems, and components important to safety so that a fire that is not promptly extinguished by the fire suppression activities will not prevent the safe shutdown of the plant.

3.2.1 Objective 1: Control of Combustibles and Potential Ignition Sources TVA stated that the combustible loading for RI is low with RCP lubricating oil being the majority of the combustible load. The remainder of the in situ combustible load consists of insulation on cables in trays and small quantities of plastics associated with small control panels, telephones and junction boxes.

Regarding ignition sources, the RCP and CROM cooler are the major equipment located in each quadrant that could be considered ignition sources.

TVA stated that each RCP is provided with a seismically designed oil collection system per Appendix R, Section 111.0. Further, each RCP is provided with a fire detection system and an automatic water-based fire suppression system. TVA stated that a postulated fire on an RCP would be detected by the detection system that would charge the suppression system and alarm in the Main Control Room.

TVA stated that a CROM cooler unit consists of a plenum, three air cooling coils and two vane axial fans and their motors. Further, each unit is seismically designed. TVA stated that a postulated fire in a CROM cooler unit would be very small and contained within the unit. TVA concludes that the lack of combustibles associated with the unit provides assurance that no components outside the unit would be damaged by a fire in the unit.

TVA stated that none of the other combustible materials in RI are associated with an ignition source. TVA provided a discussion that concluded that motor operated valve motors are not ignition sources that would propagate beyond themselves in Part VII, Section 2.9.0 of the FPR.

TVA stated that these containment quadrants have stronger combustible controls than other plant areas, since these areas are considered combustible control zones. In addition, these areas are inaccessible during power operations and access would involve the climbing of

ladders for entry, which reduces the likelihood of accumulating transient combustibles and unexpected ignition sources.

TVA provided a discussion that concluded fires in adjacent rooms would not affect the FSSD equipment in RI, due to the arrangement, types, and quantities of combustibles in the adjoining rooms. TVA also provided a similar discussion that concluded that a fire in RI would not affect the FSSD equipment in the adjoining rooms.

TVA has proposed no changes to this element.

3.2.2 Objective 2: Fire Detection and Suppression TVA stated that each RCP is equipped with a fire detection system and a water based automatic suppression system. TVA further stated that the detection systems alarm in the Main Control Room and charge the associated suppression systems.

There is no other automatic suppression or detection in RI. For manual fire fighting, a standpipe and hose station is provided in each RI quadrant.

TVA has proposed no changes to this element.

3.2.3 Objective 3: Post-Fire Safe Shutdown Under the defense in depth philosophy, if a fire does occur that is not quickly suppressed, minimum separation criteria for redundant cables and equipment ensure that post-fire safe shutdown can be achieved. TVA identified the following deviations from separation criteria that require NRC approval.

3.2.3.1 Requested Approval: Steam Generator Temperature Indication Configuration In its supplement dated July 22, 2016, TVA stated that at the interface of quadrants Rl-2 and Rl-3 the cables for cold- and hot-leg temperature instruments for steam generator 1 have less than 20 feet horizontal separation from the corresponding instruments for steam generator 3.

Required and alternative systems TVA indicated that level and temperature indication from two steam generators are needed to assure post-fire safe shutdown. TVA further indicated that steam generator level instrumentation is properly separated.

TVA stated that for a fire in a particular quadrant, the following are credited:

• Rl steam generators 2 and 3

• Rl steam generators 3 and 4

• Rl steam generators 1 and 4

• Rl steam generators 2 and 3 TVA stated that the temperature indication for steam generators 1 and 3 are separated by at least 17 feet 11 inches at the boundary of Rl-2 and Rl-3. As described in Sections 3.2.1 and 3.2.2 above, for credible ignition sources, either fires are not expected to leave their components, such as the CROM coolers, or the component is equipped with an automatic suppression system, as for the RCPs.

TVA concluded that, because of the limited amount of ignition sources and combustibles present, a fire on the boundary would not damage cables for temperature indication for both steam generators 1 and 3, and if either is damaged, the other is available, along with steam generator 4 to achieve safe shutdown, as described above.

Conclusion The NRC staff concludes that this configuration is acceptable because of the presence of fire detection and automatic suppression on the only large source of combustibles (the RCPs), the otherwise limited combustible loading, the lack of ignition sources, and other defense in depth features described in Sections 3.2.1 and 3.2.2 above. Therefore, the NRC staff concludes that there is reasonable assurance that fire damage would be limited such that systems necessary to achieve and maintain post-fire safe shutdown conditions are available in accordance with Section 111.G.d of Appendix R to 10 CFR Part 50.

3.2.3.2 Requested Approval: Reactor Vessel Head Vent Cables and Pressurizer PORV and Cables Configuration TVA stated that the cables for the reactor head vent valves have less than 20 feet horizontal separation from the pressurizer PORV cables.

Required and alternative systems TVA indicated that either the head vent or pressurizer PORV was needed to depressurize the RCS if necessary to assure post-fire safe shutdown.

TVA stated that the cables for the reactor head vent valves have at least 17 feet of horizontal separation from the pressurizer PORV cables, which are located at the top of the pressurizer.

As described in Sections 3.2.1 and 3.2.2 above, for credible ignition sources, either fires are not expected to leave their components, such as the CROM coolers, or the component is equipped with an automatic suppression system, as for the RCPs. TVA stated that both the PORV and head vent cables are run in conduit.

TVA stated that fire damage to the PORV cables would prevent operation of the PORV, but would not cause spurious opening. In addition, TVA stated that power is removed from the head vent valve circuits during normal plant operation to prevent the head vents from spuriously opening, but power can be restored in a timely manner to allow for head vent control if the PORV control is lost.

TVA concluded that, because of the limited amount of combustibles, and the lack of ignition sources near the pressurizer, a fire would not damage both the PORV cables and the head vent valve cables.

Conclusion The NRC staff concludes that this configuration is acceptable because of the presence of fire detection and automatic suppression on the only large source of combustibles (the RCPs), the otherwise limited combustible loading, the lack of other ignition sources, cables run in conduit, and other defense in depth features described Sections 3.2.1 and 3.2.2 above. Therefore, the NRC staff concludes that there is reasonable assurance that fire damage would be limited such that systems necessary to achieve and maintain post-fire safe shutdown conditions are available in accordance with Section 111.G.d of Appendix R to 10 CFR Part 50.

3.2.3.3 Requested Approval: CROM Cooler Cable and LCC Cable Configuration TVA stated that in zone Rl-2, there is less than 20 feet of horizontal separation between the cables for LCC 1A-A and CROM cooler 1C-A.

Required systems and alternatives TVA stated that in addition to the four CROM coolers, containment cooling is provided by four LCCs, two of which are located in each of the adjoining containment fan rooms (rooms RF1 and RF2). TVA stated that to maintain containment cooling, either three LCCs or two LCCs and two CROM coolers are required.

The four CROM coolers designated: 1A-A, 1B-B, 1C-A, and 10-B. Similarly, the LCCs are designated 1A-A, 1B-B, 1C-A, and 10-B. In its supplement dated July 22, 2016, TVA indicated that the following are credited for a fire in a quadrant:

• Rl LCCs 1B-B and 1C-A and CROM coolers 1B-B and 1C-A

• Rl either o LC Cs 1A-A, 1B-B, and 1C-A; or o LCCs 1B-B and 1C-A and CROM coolers 10-B and 1C-A

• Rl LCCs 1A-A, 1B-B, and 1C-A

• Rl LCCs 1A-A, 1B-B, and 1C-A TVA stated that there is at least 10 feet of horizontal separation between the cables for LCC 1A-A and CROM cooler 1C-A. As described in Sections 3.2.1 and 3.2.2 above, for credible ignition sources, either fires are not expected to leave their components, such as the CROM coolers, or the component is equipped with an automatic suppression system, as for the RCPs.

TVA concluded that because of the limited amount of combustibles present, a fire would not damage the cables for both LCC 1A-A and CROM cooler 1C-A, and if either is damaged, the other is available, as indicated above, to achieve safe shutdown.

Conclusion The NRC staff concludes that this configuration is acceptable because of the presence of fire detection and automatic suppression on the only large source of combustibles (the RCPs), the otherwise limited combustible loading, the lack of ignition sources, and other defense in depth features described in Sections 3.2.1 and 3.2.2 above. Therefore, the NRC staff concludes that there is reasonable assurance that fire damage would be limited such that systems necessary to achieve and maintain post-fire safe shutdown conditions are available in accordance with Section 111.G.d of Appendix R to 10 CFR Part 50.

3.3 NRC Staff Conclusion

Based on the information and analyses presented in the preceding sections, the NRC staff concludes that, for the interactions described above, there is reasonable assurance that fire damage would be limited such that systems necessary to achieve and maintain post-fire safe shutdown conditions are available in accordance with Section 111.G of Appendix R to 10 CFR Part 50.

3.4 Revision to License Condition 2.F Paragraph 2.F of Facility Operating License No. NPF-90 for WBN Unit 1, provides a license condition to require the licensee to fully implement and maintain in effect all provisions of the approved fire protection program. The current license condition for WBN Unit 1 states:

TVA shall implement and maintain in effect all provisions of the approved fire protection program as described in the Fire Protection Report for the facility, as approved in Appendix FF Section 3.5 of Supplement 18 and Supplement 29 of the SER (NUREG-0847) subject to the following provision:

TVA may make changes to the approved fire protection program without prior approval of the Commission only if those changes would not adversely affect the ability to achieve and maintain safe shutdown in the event of a fire.

In its letter dated February 23, 2016, the licensee proposed to modify Paragraph 2.F to incorporate this amendment. The revised license condition in Paragraph 2.F of Facility Operating License No. NPF-90 for WBN Unit 1 would state:

TVA shall implement and maintain in effect all provisions of the approved fire protection program as described in the Fire Protection Report for the facility, as approved in Appendix FF Section 3.5 of Supplement 18 and Supplement 29 of the SER (NUREG-0847) and in Amendment 108 subject to the following provision:

TVA may make changes to the approved fire protection program without prior approval of the Commission only if those changes would not adversely affect the ability to achieve and maintain safe shutdown in the event of a fire.

The change to the license condition reflects the change to the approved fire protection program based on the issuance of this license amendment. This is an administrative change to the license condition to reflect this license amendment that is applicable to the fire protection program and, therefore, is acceptable to the NRC staff.

4.0 STATE CONSULTATION

In accordance with the Commission's regulations, the Tennessee State official was notified of the proposed issuance of the amendment. The State official had no comments.

5.0 ENVIRONMENTAL CONSIDERATION

The amendment changes a requirement with respect to installation or use of a facility component located within the restricted area as defined in 10 CFR Part 20. The NRC staff has determined that the amendment involves no significant increase in the amounts, and no significant change in the types, of any effluents that may be released offsite, and that there is no significant increase in individual or cumulative occupational radiation exposure. The Commission has previously issued a proposed finding that the amendment involves no significant hazards consideration, and there has been no public comment on such finding (81 FR 28901, May 10, 2016). Accordingly, the amendment meets the eligibility criteria for categorical exclusion set forth in 10 CFR 51.22(c)(9). Pursuant to 10 CFR 51.22(b), no environmental impact statement or environmental assessment need be prepared in connection with the issuance of the amendment.

6.0 CONCLUSION

The Commission has concluded, based on the considerations discussed above, that: (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) there is reasonable assurance that such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.

Contributor: Charles Moulton Date: December 12, 2016

ML16307A013 *via memo OFFICE NRR/DORL/LPL2-2/PM NRR/DORL/LPL2-2/LA NRR/DRA/AFPB/BC* OGC NAME RSchaaf BClayton GCasto DRoth DATE 11/30/2016 11/30/2016 10/25/2016 11/18/2016 OFFICE NRR/DORL/LPL2-2/BC(A) NRR/DORL/LPL2-2/PM NAME JDion RSchaaf DATE 12/12/2016 12/12/2013